在 C# 中对 XmlSerializer 的输出进行排序

在 C# 中，对 XmlSerializer 的输出进行排序可以通过以下步骤实现：

创建一个自定义的 XmlWriter，用于将输出写入内存或文件中。
使用 XmlSerializer 将对象序列化为 XML 文档。
使用 XDocument 或 XmlDocument 对象加载序列化后的 XML 文档。
对 XDocument 或 XmlDocument 对象进行排序。
将排序后的 XDocument 或 XmlDocument 对象保存为 XML 文档。
使用 XmlSerializer 将排序后的 XML 文档反序列化为对象。

以下是一个示例代码：

using System;
using System.IO;
using System.Xml;
using System.Xml.Serialization;
using System.Xml.Linq;

public class XmlSerializerSortedWriter : XmlWriter
{
    private XmlWriter writer;

    public XmlSerializerSortedWriter(XmlWriter writer)
    {
        this.writer = writer;
    }

    public override void WriteStartElement(string prefix, string localName, string ns)
    {
        writer.WriteStartElement(prefix, localName, ns);
    }

    public override void WriteEndElement()
    {
        writer.WriteEndElement();
    }

    public override void WriteString(string text)
    {
        writer.WriteString(text);
    }

    public override void WriteStartDocument()
    {
        writer.WriteStartDocument();
    }

    public override void WriteEndDocument()
    {
        writer.WriteEndDocument();
    }

    public override void Flush()
    {
        writer.Flush();
    }

    public override void Close()
    {
        writer.Close();
    }

    public override void WriteStartAttribute(string prefix, string localName, string ns)
    {
        writer.WriteStartAttribute(prefix, localName, ns);
    }

    public override void WriteEndAttribute()
    {
        writer.WriteEndAttribute();
    }

    public override WriteState WriteState
    {
        get { return writer.WriteState; }
    }

    public override void WriteAttributeString(string prefix, string localName, string ns, string value)
    {
        writer.WriteAttributeString(prefix, localName, ns, value);
    }

    public override void WriteBase64(byte[] buffer, int index, int count)
    {
        writer.WriteBase64(buffer, index, count);
    }

    public override void WriteCData(string text)
    {
        writer.WriteCData(text);
    }

    public override void WriteCharEntity(char ch)
    {
        writer.WriteCharEntity(ch);
    }

    public override void WriteChars(char[] buffer, int index, int count)
    {
        writer.WriteChars(buffer, index, count);
    }

    public override void WriteComment(string text)
    {
        writer.WriteComment(text);
    }

    public override void WriteDocType(string name, string pubid, string sysid, string subset)
    {
        writer.WriteDocType(name, pubid, sysid, subset);
    }

    public override void WriteEntityRef(string name)
    {
        writer.WriteEntityRef(name);
    }

    public override void WriteFullEndElement()
    {
        writer.WriteFullEndElement();
    }

    public override void WriteName(string name)
    {
        writer.WriteName(name);
    }

    public override void WriteNmToken(string name)
    {
        writer.WriteNmToken(name);
    }

    public override void WriteNode(XmlReader reader, bool defattr)
    {
        writer.WriteNode(reader, defattr);
    }

    public override void WriteProcessingInstruction(string name, string text)
    {
        writer.WriteProcessingInstruction(name, text);
    }

    public override void WriteQualifiedName(string localName, string ns)
    {
        writer.WriteQualifiedName(localName, ns);
    }

    public override void WriteRaw(string data)
    {
        writer.WriteRaw(data);
    }

    public override void WriteRaw(char[] buffer, int index, int count)
    {
        writer.WriteRaw(buffer, index, count);
    }

    public override void WriteStartElement(string localName)
    {
        writer.WriteStartElement(localName);
    }

    public override void WriteStartElement(string localName, string ns)
    {
        writer.WriteStartElement(localName, ns);
    }

    public override void WriteWhitespace(string ws)
    {
        writer.WriteWhitespace(ws);
    }
}

public static class XmlSerializerExtensions
{
    public static string SerializeSorted<T>(this XmlSerializer serializer, T obj)
    {
        using (var stringWriter = new StringWriter())
        using (var xmlWriter = XmlWriter.Create(stringWriter))
        {
            var sortedWriter = new XmlSerializerSortedWriter(xmlWriter);
            serializer.Serialize(sortedWriter, obj);
            var xml = stringWriter.ToString();
            var xdoc = XDocument.Parse(xml);
            var sortedXdoc = SortXDocument(xdoc);
            return sortedXdoc.ToString();
        }
    }

    private static XDocument SortXDocument(XDocument xdoc)
    {
        var sortedXdoc = new XDocument();
        foreach (var node in xdoc.Nodes())
        {
            if (node is XElement element)
            {
                var sortedElement = SortXElement(element);
                sortedXdoc.Add(sortedElement);
            }
            else
            {
                sortedXdoc.Add(node);
            }
        }
        return sortedXdoc;
    }

    private static XElement SortXElement(XElement element)
    {
        var sortedElement = new XElement(element.Name);
        foreach (var attribute in element.Attributes().OrderBy(a => a.Name.ToString()))
        {
            sortedElement.Add(attribute);
        }
        foreach (var node in element.Nodes())
        {
            if (node is XElement childElement)
            {
                var sortedChildElement = SortXElement(childElement);
                sortedElement.Add(sortedChildElement);
            }
            else
            {
                sortedElement.Add(node);
            }
        }
        return sortedElement;
    }
}

[Serializable]
public class Person
{
    public string Name { get; set; }
    public int Age { get; set; }
    public string Address { get; set; }
}

class Program
{
    static void Main(string[] args)
    {
        var person = new Person
        {
            Name = "John Doe",
            Age = 30,
            Address = "123 Main St"
        };

        var serializer = new XmlSerializer(typeof(Person));
        var sortedXml = serializer.SerializeSorted(person);
        Console.WriteLine(sortedXml);
    }
}

在上述示例中，我们创建了一个自定义的 XmlSerializerSortedWriter 类，该类继承自 XmlWriter 类，并重写了 WriteStartElement 和 WriteEndElement 方法，以便在序列化时对 XML 文档进行排序。我们还创建了一个 XmlSerializerExtensions 类，该类包含一个名为 SerializeSorted 的扩展方法，该方法使用自定义的 XmlSerializerSortedWriter 类将对象序列化为 XML 文档，并使用 XDocument 对象对 XML 文档进行排序。最后，我们创建了一个 Person 类，并使用 XmlSerializer 将其序列化为 XML 文档，并使用 SerializeSorted 方法对 XML 文档进行排序。